1. Field of the Invention
The invention is related in general to cleaning tape drives. More particularly, the invention consists of a novel system and method for determining when an input/output transducer of a tape drive is clean.
2. Description of the Prior Art
Storage automation products, such as the IBM 3584 Ultra Scalable Tape Library, provided by International Business Machines (“IBM”)®, include tape drives, one or more robotic accessors, and a plurality of storage cells for tape cartridges. The tape drives traditionally have input/output (“I/O”) transducers known as a tape head or an I/O head. During use, the I/O transducer inside of each tape drive can become contaminated with debris. This requires that the I/O transducer be cleaned with a cleaner tape.
In U.S. Pat. No. 4,893,209, Mohammed Siddiq describes a multifunctional cleaning tape used as part of a video cassette for cleaning the magnetic head of a video cassette recorder (“VCR”) and providing diagnostic/instructional information to a user. The tape includes a first, non-magnetic cleaning segment for cleaning the magnetic head followed by a magnetic diagnostic segment containing prerecorded diagnostic information. The diagnostic information includes information relating to the cleanliness of the magnetic head and for adjusting the VCR for improved visual and audio output and tape tracking. However, Siddiq does not disclose reading servo information as a means of testing the cleanliness of the tape servo head.
In U.S. Pat. No. 5,841,613, Robert DeMaster et al. disclose a cassette having a leader and recordable tape which cleans the various components of the tape path in VCRs by dry scrubbing. Interactive diagnostic and instructional material is recorded on the tape to instruct the operator about the cleaning operation to enable the operator to evaluate progress of the head cleaning operation. However, DeMaster also does not disclose reading servo information as a means of testing the cleanliness of the tape servo head. While the prior art teaches testing for clean data-head elements, none of the prior art teaches testing for clean servo-head elements. Accordingly, it would be advantageous to have a system for cleaning and verifying the servo-head elements are clean utilizing a single tape cartridge.
The type of cleaning media and cleaning motion used to clean a drive head varies with the type of contaminant deposited on the drive head. Additionally, the time allowed to clean a drive head may be limited by host and system timeout conditions. Yet another consideration for cleaner cartridges is that a segment of relatively high-strength leader tape is necessary to allow threading of the tape into the cleaner cartridge during removal and replacement (“R&R”) procedures. If this leader tape is made from highly abrasive material, traditional algorithms for cleaning drive-heads may inadvertently overclean and damage the drive head. These same cleaning algorithms could produce overcleaning and damage to the drive head utilizing other portions of the cleaning tape, if the entire cleaner tape was made using a highly abrasive material. However, if the abrasiveness of the entire cleaner tape is reduced, the effectiveness of the cleaner tape would likewise be reduced and the time to clean difficult contaminants may be insufficient. Therefore, it would be advantageous to utilize a cleaner tape that can remove multiple types of contaminants utilizing multiple types of cleaner without overcleaning and damaging the drive and or requiring an extended period of time to complete.